One very common error for an FPV Rookie is to buy antennas with the wrong connector for their video transmitter/receiver. So in this article we will show you the difference between the two connectors, SMA and RP-SMA.
SMA (stands for Sub-Miniature Version A) connectors are coaxial RF connectors developed in the 1960s
The RP in RP-SMA simply stands for reverse polarised, so the pin is on the female side instead of the male. This probably makes no sense so here’s a picture that illustrates it better than we can.
The reason RP-SMA exists was to comply with specific local regulations. The manufacturers had to make a new non-standard antenna connector for their WiFi devices that was hard to find replacements for (as they were all regular SMA before that), to prevent consumers from connecting antennas with gain and therefore breach compliance (from Wikipedia). So they just simply swapped the locations of the center pin and hole between the male and female connectors.
There is no “better” connector, however Boscam and TBS tend to use RP-SMA, whereas Fatshark and ImmersionRC use SMA.